Oh there is a difference.
For once the eyes you mentioned, I agree. Then there is the lack of pale skin (he looks way to reddish and healthy, like he has high blood pressure or had a sunburn). And his beard is grey instead of white.
welli agree on the skin tone, but for me is not a problem becouse 1) i like this better and 2) other witchers lik eskel and lambert dont seem to have this problem, so it only made geralt even more wierd in comparison wich is a thing i don't find necessary
on the other hand beard..you see i don't know if the devs actually knew this when they chose to make it darker but they got it right. you see in natures human being have a very different texture and complexion when we talk about "hair" ont only from a man to another obviously but even on the same person there is a variation and it's quit significant too. for example the hair located on the scalp of a persona are divided in two macro zones ( actually many more but it would be too long and complex to explain so let's just say 2) and we will call them front-mid zone and crown-back zone. now starting fro the hairline and proceding all way to the back hair will actually progressively be thicker and ticker in number and posses a higer and higer caliber the more you proceed to the back. this is a process called miniaturization and it's someting that occurs naturally starting when seaxual maturity is reached by the human body until it dies and it's the reason why when you are 30 years old chances are your hairline will not look the same as when you were 18 for example and when you are 80 your hair will not look the same as when you were 30. in some cases some genetically predisposed people could have this miniaturization process proceed at a very high sppee compared to other people no predisposed and this is called androgenetic alopecia or more commonly "getting bald" thing is even if you aren't suffering what is commonly called ( incorrectly ) hair loss ( becouse you aren't losing hair, you canno loose hair unleast there is a big cicatrization process going on in that area after a major wound or trauma of chemical nature,or you get sevely burnt etc.) but other than that you are not losing hair per se they are just miniaturizing faster than thay should. now by "miniaturization" we don't intend ONLY the caliber and general lengt of the hair being lesser and lesser in time but they also loose more and more pigmentation untile they become so tiny and clear they resoult invisible to the naked eye ( bald spots ) but in fact chances are you sill posses hair in the bald spots they are just "invisible" . since this process is always valid in all human beings and the only variable is the time needed for this process to come to a completation ( meaning that if we could all live forever we would evantually be all completly bald,no exeption man and woman alike) even mans ( or womans ) not experiencing a severe miniaturization in theyr yound to middle age years will still have thinnier and slighlty less pigmented hair in the front-middle zone of theyr scalp compared to the crown-back zone. this is becouse the miniaturization process starts from the fronts and proced all the way to the back in time. now hair we have on our haads are not the only hair we have, in fact we are covered in hair in almost 100% of our bodies. the difference between they "kind" and "quality" of hair is determined greatly by the function they are supposed to have and this varies from spot to spot in our bodies like for example the hair on our heads ar diffrent form the hair in our armpits that at the same time are different from our eybrows hair thet at the same time are aslo different from our eyeleshes hair and so on. the difference consists not only in the maximum lenght achivable by that particular kind of hair in that zone of the body and the time required for it to grow to a certain lengt but also by the general "quality" of it meaning texture,caliber and pigmentation. body hair in general,but particularly eyebrows and beard are always mutch larger in caliber and more strongly pigmented if compared to other hair in the body and particularly on the head. we laso gradually loose pigmentation in our hair ( all of them all over the body ) duing to aging process and so with dued proportions taken in to account obviously, having said that, it makes perfect sense for a person with completly white hair witch is not super old to have slighlty daker beard and eybrows ( or body hair ) n fact if you see this is true even in the first picture ( orignial geralt model ) the eybrows and beard alone are greysh withe not milk white like the hair.
now you may tell that albinos ( like geralt ) are an exeption to this becouse they are born without any sort of pigment in theyr hair ( al of them ) so geralt sholud also have matching colored eybrows and beard. and you would be correct if it wasen't that gerat is NOT a natural albino but and induced one ( from what i see it's like the aging process, even if only regarding the pigmentation is gone incredibly fast in a short amount of time, thanks to the mutations ) and probably it wasen't strong enough to completly wipe all the pigment from geralt since he naturally posses it genetically.
the proof of geralt not being an albino from the start is that albinos ( human albinos at least ) are generally hairless. they don't posses beards or body hairs if not in one or two key zones, and not even always. but to my knowlegde they don't have beards ( they do have eybrows, eylashes and obviosuly hair on the head but they tend to be naturally "weaker" less thick ,of minor caliber, more subject to damage if compared to the pigmented parallel )
so in short no. geralt having grey beard and eybrows is 100% genetically accurate since he is and "induced albino"
